Dead, inactive or negative workstations of a spinning or twisting machine, advantageously a ring spinning machine, in which yarn breaks can be automatically eliminated by a yarn-starting carriage, can also be registered automatically.
Any workstation at which, after a yarn break, a predetermined number of successive yarn break elimination attempts by the yarn-starting carriage have failed, is automatically registered in a memory as a dead workstation and the yarn-starting carriage at each of the workstations which is registered as dead performs no yarn break elimination attempts.
By "workstation" I mean a spinning station or a twisting station of the spinning and/or twisting machine involved. Yarn is made by spinning and/or twisting at each workstation.
The spinning machine can be advantageously a ring spinning machine or, if necessary, another spinning machine such as a bell spinning machine, a top spinning machine or the like. The twisting machine can advantageously be a matter of a ring twisting machine but, can be also another type of twisting machine.
In one known process of this kind (German Pat. No. 24 54 721), every workstation at which a predetermined number of successive yarn break elimination attempts by the yarn-starting carriage during its idle time fail, that workstation is registered as dead (therein called "negative" workstations) and all registered dead workstations are passed by the yarn-starting carriage without a yarn-starting attempt.
The registering of the dead workstations can be undertaken in a central memory. On running of the yarn-starting carriage along the spinning or twisting machine, before arrival of the yarn-starting carriage at the next workstation, the memory is read to determine whether this next workstation is registered as "dead," i.e. that means registered as a dead workstation and, when this is the case, the yarn-starting carriage is caused to pass by it without halting.
A dead workstation then usually is present when because of some reason a yarn break cannot be fundamentally eliminated and/or because of missing roving, or yarn tangle on a set of drafting rolls and, in ring spinning or ring twisting machines, operation breaks.
When the problem at one of these workstations registered as dead is eliminated and thus yarn can be spun or twisted again at it, the registry of this workstation as "dead" in the memory must be erased. It is conceivable that for this purpose at each workstation a switch operable by an operator manually for erasing its registration as "dead" is located. That is, however, a very expensive construction.
Alternatively the operator goes to a central control station which is located at the end of the machine or on the yarn-starting carriage and there erases the registration of that workstation as dead by inputting the number or other code of this workstation. In this case the number of the workstations can however be delivered incorrectly or erroneously.